U.S. patent application number 11/070798 was filed with the patent office on 2005-09-08 for thermoelectric generator.
Invention is credited to Inaoka, Hiroya, Mori, Rentaro, Yamaguchi, Hiroo, Yamanaka, Yasutoshi.
Application Number | 20050194034 11/070798 |
Document ID | / |
Family ID | 34431658 |
Filed Date | 2005-09-08 |
United States Patent
Application |
20050194034 |
Kind Code |
A1 |
Yamaguchi, Hiroo ; et
al. |
September 8, 2005 |
Thermoelectric generator
Abstract
A thermoelectric generator has a plurality of hot-side heat
source portions, a plurality of cold-side heat source portions, a
thermoelectric element, a hot-side communicator and a cold-side
communicator. Hot fluid flows in the plurality of hot-side heat
source portions, and cold fluid colder than the hot fluid flows in
the plurality of cold-side heat source portions. The heat source
portions are alternately stacked in such a manner of interposing
the thermoelectric element between the hot-side heat source portion
and the cold-side heat source portion. The hot-side communicator
communicates the hot-side heat source portions, and the cold-side
communicator communicates the plurality of cold-side heat source
portions. Each of the hot-side communicator and the cold-side
communicator has a distance adjuster for adjusting distances
between the hot-side heat source portions and the cold-side heat
source portions so as to bring them in contact with the
thermoelectric elements in the stacking direction thereof.
Inventors: |
Yamaguchi, Hiroo;
(Toyohashi-city, JP) ; Yamanaka, Yasutoshi;
(Kariya-city, JP) ; Inaoka, Hiroya; (Toyota-city,
JP) ; Mori, Rentaro; (Kasugai-city, JP) |
Correspondence
Address: |
HARNESS, DICKEY & PIERCE, P.L.C.
P.O. BOX 828
BLOOMFIELD HILLS
MI
48303
US
|
Family ID: |
34431658 |
Appl. No.: |
11/070798 |
Filed: |
March 2, 2005 |
Current U.S.
Class: |
136/205 |
Current CPC
Class: |
H01L 35/30 20130101 |
Class at
Publication: |
136/205 |
International
Class: |
H01L 035/30 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 4, 2004 |
JP |
2004-061383 |
Claims
What is claimed is:
1. A thermoelectric generator comprising: a plurality of hot-side
heat source portions in which hot fluid flows; a plurality of
cold-side heat source portions in which cold fluid colder than the
hot fluid flows and alternately stacked together with the plurality
of hot-side heat source portions; a thermoelectric element
interposed between the hot-side heat source portion and the
cold-side heat source portion; a hot-side communicator
communicating the plurality of hot-side heat source portions; and a
cold-side communicator communicating the plurality of cold-side
heat source portions, wherein each of the hot-side communicator and
the cold-side communicator has a distance adjuster for adjusting
distances between the hot-side heat source portions and the
cold-side heat source portions so as to bring them in contact with
the thermoelectric elements in the stacking direction thereof.
2. The thermoelectric generator according to claim 1, wherein each
of the communicators has: a one-side pipe located on one side of
each of the heat source portions and connected by a sealing member;
another-side pipe located on the other side of each of the heat
source portions and inserted into the one-side pipe so as to
implement the distance adjuster; and a sealing member disposed
between an inner circumference of the one-side pipe and an outer
circumference of the other-side pipe.
3. The thermoelectric generator according to claim 1, wherein each
of the communicators has: a pipe disposed between the heat source
portions; and a bellows disposed at longitudinal end of the pipe
and extendible and shrinkable in a longitudinal direction of the
pipe so as to implement the distance adjuster.
4. The thermoelectric generator according to claim 1, wherein: the
hot-side communicator is disposed not to be in contact with the
cold-side heat source portions; and the cold-side communicator is
disposed not to be in contact with the hot-side heat source
portions.
5. The thermoelectric generator according to claim 1, further
comprising: a vacuum container for keeping an internal space
thereof vacuum and enclosing the heat source portions, the
thermoelectric elements and the communicators.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application is based upon and claims the benefit of
priority of Japanese Patent Application No. 2004-061383 filed on
Mar. 4, 2004, the content of which is incorporated herein by
reference.
FIELD OF THE INVENTION
[0002] The present invention relates to a thermoelectric generator
that generates an electric power by Seebeck effect applying a
temperature difference to a thermoelectric element.
BACKGROUND OF THE INVENTION
[0003] JP-10-136672-A discloses a conventional thermoelectric
generator having a plurality of heat exchangers for heating and for
cooling alternately stacked and thermoelectric generation modules
disposed between the heat exchangers. The heat exchangers are
communicated to each other by an emission gas supply pipe at one
end side thereof and by an emission gas emission pipe at another
end side thereof so that the emission gas flows through all of the
heat exchangers. Specifically, each of the emission gas supply pipe
and the emission gas emission pipe has a plurality of branch pipes
toward the plurality of the heat exchanger for heating. A branch
pipe of the emission gas supply pipe and that of the emission gas
emission pipe are connected to and integrally formed with each of
the heat exchanger for heating.
[0004] The heat exchanger for cooling has a structure similar to
that of the above description. The heat exchangers are communicated
to each other by branch pipes of a cooling water supply pipe and by
branch pipes of a cooling water emission pipe so that cooling water
flows through all of the heat exchangers.
[0005] To reduce a thermal transfer resistance caused by surface
asperities (surface roughness) of the heat exchangers in contact
with the thermoelectric generation modules, helium gas is filled
between the thermoelectric generation modules and the heat
exchangers. Further, to apply a uniform pressure to the heat
exchangers for heating, the thermoelectric generation modules and
the heat exchangers for cooling in a stack, a pressurizing means (a
bellows) is provided for pressurizing a fluid media (air, nitrogen,
silicon oil, etc.).
[0006] However, in the above conventional art, the thermoelectric
generator has an extremely complicated configuration as a whole, by
filling helium gas and by setting the pressurizing means (the
bellows). Especially, each of the heat exchangers are integrally
connected by a plurality of branch pipes of the supply pipes and
the emission pipes, making the clearances between the heat
exchangers vary, and leading the pressurizing means to a
complicated configuration for assembling the heat exchangers and
the thermoelectric generation modules in secure contact with each
other, predicated on deforming them.
SUMMARY OF THE INVENTION
[0007] The object of the present invention, in view of the above
issues, is to provide a thermoelectric generator having multi-layer
capable of bringing thermoelectric elements, hot-side heat source
portion and cold-side heat source portion in well contact with each
other, without heavy configurations.
[0008] To achieve the above object, a thermoelectric generator
according to the present invention comprises a plurality of
hot-side heat source portions, a plurality of cold-side heat source
portions, a thermoelectric element, a hot-side communicator and a
cold-side communicator. Hot fluid flows in the plurality of
hot-side heat source portions, and cold fluid colder than the hot
fluid flows in the plurality of cold-side heat source portions. The
hot-side heat source portions and the cold-side heat source
portions are alternately stacked in such a manner of interposing
the thermoelectric element between the hot-side heat source portion
and the cold-side heat source portion. The hot-side communicator
communicates the plurality of hot-side heat source portions, and
the cold-side communicator communicates the plurality of cold-side
heat source portions. Each of the hot-side communicator and the
cold-side communicator has a distance adjuster for adjusting
distances between the hot-side heat source portions and the
cold-side heat source portions so as to bring them in contact with
the thermoelectric elements in the stacking direction thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Other features and advantages of the present invention will
be appreciated, as well as methods of operation and the function of
the related parts, from a study of the following detailed
description, the appended claims, and the drawings, all of which
form a part of this application. In the drawings:
[0010] FIG. 1 is a schematic diagram showing an entire structure
including an engine according to a first embodiment of the present
invention;
[0011] FIG. 2 is a front view showing an exterior appearance of a
thermoelectric generator in FIG. 1;
[0012] FIG. 3 is a plan view showing an exterior appearance of a
thermoelectric generator in FIG. 1;
[0013] FIG. 4A is a plan view showing a high temperature side heat
source portion (for an uppermost layer);
[0014] FIG. 4B is a front view showing a high temperature side heat
source portion (for an uppermost layer);
[0015] FIG. 5A is a plan view showing a high temperature side heat
source portion (for a general layer);
[0016] FIG. 5B is a front view showing a high temperature side heat
source portion (for a general layer);
[0017] FIG. 6A is a plan view showing a low temperature side heat
source portion (for an uppermost layer);
[0018] FIG. 6B is a front view showing a low temperature side heat
source portion (for an uppermost layer);
[0019] FIG. 7A is a plan view showing a low temperature side heat
source portion (for a general layer);
[0020] FIG. 7B is a front view showing a low temperature side heat
source portion (for a general layer);
[0021] FIG. 8 is an exploded diagram showing an assembling way of
the high temperature side heat source portions, the low temperature
side heat source portions and thermoelectric elements;
[0022] FIG. 9 is a front vertical-sectional view showing an
exterior appearance of a thermoelectric generator according to a
second embodiment;
[0023] FIG. 10 is an exploded vertical-sectional diagram showing an
assembling way of the high temperature side heat source portions
and the low temperature side heat source portions in FIG. 9;
[0024] FIG. 11 is a front view showing an exterior appearance of a
thermoelectric generator according to a third embodiment;
[0025] FIG. 12 is a schematic diagram showing an entire structure
including an engine according to a first other embodiment;
[0026] FIG. 13 is a schematic diagram showing an entire structure
including an engine according to a second other embodiment; and
[0027] FIG. 14 is a schematic diagram showing an entire structure
including an engine according to a third other embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
First Embodiment
[0028] A thermoelectric generator 100 according to the present
invention is applied to a vehicle having a water-cooled engine 10,
wherein an electric energy is recovered from a discharged heat
energy associated with a cooling of the engine 10. First, a
fundamental structure thereof will be described with reference to
FIGS. 1 to 8. Here, FIG. 1 is a schematic diagram showing an entire
structure including the engine 10. FIGS. 2 and 3 are a front view
and a plan view showing an exterior appearance of a thermoelectric
generator 100. FIGS. 4 and 5 are plan views and front views showing
a high temperature side heat source portions 110. FIGS. 6 and 7 are
plan views and front views showing a low temperature side heat
source portions 120. FIG. 8 is an exploded diagram showing an
assembling way of the high temperature side heat source portions
110, the low temperature side heat source portions 120 and
thermoelectric elements 130.
[0029] As shown in FIG. 1, the engine 10 has an engine coolant
circuit 20 and a radiator 21. A water pump 11 circulates coolant in
the engine 10 through the engine coolant circuit 20 and the
radiator 21. Here, the water pump 11 is an engine driven type pump
run by the driving force of the engine 10. A heat radiation by the
radiator 21 cools the coolant so as to control the operation
temperature of the engine 10 adequately. Incidentally, the engine
coolant circuit 20 has a bypass 22 for detouring the coolant around
the radiator 21 and a thermostat (a flow amount control valve) 23
for adjusting a flow amount of the coolant flowing through the
bypass 22. When the temperature of the coolant is not over a
predetermined value (for example, 90.degree. C.), the thermostat 23
shuts a flow of the coolant through the radiator 21 so as to flow
the coolant through the bypass 22 to prevent the coolant from being
excessively cooled.
[0030] The engine coolant circuit 20 has a hot coolant inflow pipe
31 that branches at a node between a point upstream of the radiator
20 and the bypass 22, and a hot coolant outflow pipe 32 that
branches at a node between a point downstream of the radiator 21
and the thermostat 23. The hot coolant inflow pipe 31 and the hot
coolant outflow pipe 32 are connected to the hot-side heat source
portion 110 of the thermoelectric generator 100, which will be
described below. That is, while the thermostat 23 opens to a side
of the radiator 21, a portion of the hot coolant (a coolant having
a temperature between 90.degree. C. and 100.degree. C. in
correspondence with "hot fluid" of the present invention) flowing
through the radiator 21 is introduced via the hot coolant inflow
pipe 31 and the hot coolant outflow pipe 32 to the hot-side heat
source portion 110.
[0031] The thermoelectric generator 100 has a cold-side radiator 43
independent of the radiator 21, and a cold coolant inflow pipe 41
and a cold coolant outflow pipe 42 are connected to the cold-side
radiator 43 and a cold-side heat source portion 120 of the
thermoelectric generator 100, which will be described below. A
water pump 44 is disposed on a way of the cold coolant outflow pipe
42. The water pump 44 operates so as to flow cold coolant in the
cold-side radiator 43 (a coolant having a temperature between
30.degree. C. and 40.degree. C. in correspondence with "cold fluid"
in the present invention) through the cold-side heat source portion
120.
[0032] As shown in FIGS. 2 and 3, the thermoelectric generator 100
is formed in such a manner that thermoelectric elements 130, which
is conventional ones generating electric power by Seebeck effect,
are disposed between the hot-side heat source portions 110 and the
cold-side heat source portions 120 that are alternately stacked. In
this embodiment, the thermoelectric generator 100 has a nine layer
structure including two hot-side heat source portions 110, three
cold-side heat source portions 120 and four thermoelectric elements
130. A thermal-conductivity grease coating or a heat transfer sheet
is interposed between the hot-side heat source portion 110 and the
thermoelectric element 130 and between the cold-side heat source
portion 120 and the thermoelectric element 130.
[0033] A hot-side communicator 140 communicates a plurality of the
hot-side heat source portions 110 in a stacking direction thereof.
A cold-side communicator 150 communicates a plurality of the
cold-side heat source portions 120 in a stacking direction thereof.
The cold coolant flows out of the cold-side radiator 43 then flows
through the plurality of the cold-side heat source portions 120. In
the following, the stacking direction of the heat source portions
110, 120 will be referred to as an up-and-down direction as shown
in FIG. 2.
[0034] As shown in FIGS. 4 and 5, the hot-side heat source portion
110 is a container having a flat rectangular shape and formed with
a pair of plate members in such a manner of facing to each other.
The hot-side heat source portion 110 has two projections 111 at one
pair of opposing corners thereof (at a top-right and a lower-left
portions in FIG. 4A) and a bolt hole 122 for inserting a bolt 181
at a center portion thereof. Inner fins 113 are disposed in the
hot-side heat source portion 110 so as to transfer the heat of the
hot coolant to the thermoelectric elements 130 effectively.
[0035] As shown in FIG. 5, a large-diameter pipe (corresponding to
"one-side pipe" in the present invention) 141 and a small-diameter
pipe (corresponding to "other-side" pipe in the present invention)
142 are connected to the projecting portions 111 in such a manner
of communicating with an interior of the hot-side heat source
portion 110. The small-diameter pipe 142 has a groove around an
outer circumference of an upper end portion thereof. An O-ring
(corresponding to "sealing member" in the present invention) 143 is
attached on the groove.
[0036] An uppermost one of the hot-side heat source portions 110
has a hot coolant inlet pipe 144 and a hot coolant outlet pipe 145
(refer to FIGS. 4A and 4B) instead of the small-diameter pipe 142.
A lowermost one of the hot-side heat source portions 110 has no
large-diameter pipe 141 (not shown).
[0037] As shown in FIGS. 6 and 7, the cold-side heat source portion
120 is different from the above hot-side heat source portion 110 in
a point of having two projections 121 at another pair of opposing
corners (at lower-right and at upper-left portions in FIGS. 6A and
7A). The cold-side heat source portion 120 has substantially the
same structure as that of the hot-side heat source portion 110
except for the above point. The cold-side heat source portion 120
has a bolt hole 122 at a center portion thereof and inner fins 113
therein for transferring the heat of the cold coolant to the
thermoelectric elements 130 effectively.
[0038] As shown in FIG. 7, a large-diameter pipe 141 and a
small-diameter pipe 142 on which the O-ring 143 is attached are
connected to the projecting portions 121. An uppermost one of the
cold-side heat source portions 120 has a cold coolant inlet pipe
151 and a cold coolant outlet pipe 152 (refer to FIGS. 6A and 6B)
instead of the small-diameter pipe 142. A lowermost one of the
cold-side heat source portions 120 has no large-diameter pipe 141
(not shown).
[0039] The thermoelectric generator 100 is assembled as follows. As
shown in FIG. 8, the cold-side heat source portion 120, the
thermoelectric element 130, the hot-side heat source portion 110
and the thermoelectric element 130 are repeatedly stacked in turn.
The small-diameter pipe 142 of the lowermost one of the cold-side
heat source portions 120 is inserted into the large-diameter pipe
141 of another one of the cold-side heat source portions 120 just
above the lowermost one, interposing the O-ring 143 between the
inner circumference of the large-diameter pipe 141 and the outer
circumference of the small-diameter pipe 142. The large-diameter
pipe 141, the small-diameter pipe 142 and the O-ring 143 constitute
the cold-side communicator 150. The cold-side heat source portions
120 communicate with each other, and the cold coolant inlet pipe
151 and the cold coolant outlet pipe 152 open on the uppermost one
of the cold-side heat source portions 120.
[0040] Similarly, the small-diameter pipe 142 of the lowermost one
of the hot-side heat source portions 110 is inserted into the
large-diameter pipe 141 of another one of the cold-side heat source
portions 110 just above the lowermost one, interposing the O-ring
143 therebetween. The large-diameter pipe 141, the small-diameter
pipe 142 and the O-ring 143 constitute the hot-side communicator
140. The hot-side heat source portions 110 communicate with each
other, and the hot coolant inlet pipe 144 and the hot coolant
outlet pipe 145 open on the uppermost one of the hot-side heat
source portions 110.
[0041] Here, the hot-side communicators 140 and the cold-side
communicators 150 are respectively disposed at one pair and another
pair of diagonally opposing projections 111, 121 of the respective
heat source portions 110, 120. Thus, the hot-side communicators 140
are not in contact with the cold-side heat source portions 120, and
the cold-side communicators 150 are not in contact with the
hot-side heat source portions 110.
[0042] A stack of the above hot-side heat source portions 110, the
cold-side heat source portions 120 and the thermoelectric elements
130 is sandwiched between and supported by a lower plate 160 and an
upper plate 170 (respectively having pipe holes at positions
corresponding to the pipes 144, 145, 151 and 152). A plurality of
bolts 181 and nuts 182 fastens the stack and the lower and upper
plates 160, 170 applying a predetermined pressure in the
upper-and-lower direction, so as to form the thermoelectric
generator 100.
[0043] The hot coolant inlet pipe 144 of the thermoelectric
generator 100 is connected to the hot coolant inflow pipe 31, and
the hot coolant outlet pipe 145 is connected to the hot coolant
outflow pipe 32. While, the cold coolant inlet pipe 151 is
connected to the cold coolant inflow pipe 41, and the cold coolant
outlet pipe 152 is connected to the cold coolant outflow pipe
42.
[0044] Next, the operation of the thermoelectric generator 100
having the above configuration will be described. When the
thermostat 23 opens to the side of the radiator 21 by a temperature
increase of the coolant (over 90.degree. C. so as to be the hot
coolant), a portion of the hot coolant flowing through the engine
coolant circuit 20 flows through the hot coolant inflow pipe 31,
the hot coolant inlet pipe 144 of the thermoelectric generator 100,
the plurality of the hot-side heat source portions 110, the hot
coolant outlet pipe 145 and the hot coolant outflow pipe 32, then
returns to a point downstream of the radiator 21.
[0045] By the operation of the water pump 44, the cold coolant
flows through the cold-side radiator 43, the cold coolant inflow
pipe 41, the cold coolant intake pipe 151, the plurality of the
cold-side heat source portions 120, the cold coolant outlet pipe
152, the cold coolant outflow pipe 42, then returns to the
cold-side radiator 43.
[0046] Then, the thermoelectric elements 130 are exposed to a
temperature difference by the hot coolant flowing through the
hot-side heat source portion 110 and the cold coolant flowing
through the cold-side heat source portion 120 so as to generate
electric power, which is used for charging a battery (not shown)
and for operating respective supplemental appliances.
[0047] When the thermoelectric elements 130 generates electric
power, it is required that each of the hot-side heat source portion
110 and the cold-side heat source portion 120 is in contact with
the thermoelectric element 130 at a given face pressure so as to
reduce the contact thermal transmission resistance. In the present
invention, by using the above-described respective communicators
140, 150 for connecting the respective heat source portions 110,
120, the communicators 140, 150 serve for a distance adjuster 140A
that adjusts (smoothes) the dimension variation of the hot-side
heat source portions 110, the cold-side heat source portions 120
and the thermoelectric devices 130 in the upper-and-lower
direction. Thus, in the stack of hot-side heat source portions 110,
the cold-side heat source portions 120 and the thermoelectric
elements 130, the thermoelectric element 130 comes in well contact
with each of the hot-side heat source portion 110 and the cold-side
heat source portion 120 without excessive deformation. This serves
to reduce an extra structure of the pressuring means disclosed in
the prior art.
[0048] Further, it is possible to improve the assembling
workability of the thermoelectric generator 100 by stacking the
cold-side heat source portion 120, the thermoelectric element 130,
the hot-side heat source portion 110 and the thermoelectric element
130 repeatedly in turn.
[0049] It is also possible to prevent a heat transmission between
the hot-side heat source portion 110 and the cold-side heat source
portion 120, by disposing the respective communicators 140, 150 at
projections 111, 121 at one and another pairs of diagonally
opposing corners, not to bring the hot-side heat source portions
110 and the cold-side communicators 150 with each other and the
cold-side heat source portions an the hot-side communicators 140
with each other. That is, the amount of electric power generation
by the thermoelectric elements 130 is secured by keeping the
temperature difference between the both heat source portions 110,
120.
[0050] Furthermore, by using the coolant (hot coolant) of the
engine 10 for the heat source of the hot-side heat source portions
110, the thermoelectric generator 100 can use the exhaust heat of
the engine 10 effectively.
Second Embodiment
[0051] A second embodiment of the present invention is shown in
FIGS. 9 and 10. The second embodiment has a different configuration
from that of the above first embodiment in the respective
communicators 140, 150. The second embodiment adopts pipes 141a
(corresponding to "pipe" in the present invention) having bellows
142a, which extends and shrinks according to a distance between the
both ends of the pipe 141a. The bellows 142a serves as the distance
adjuster 140A.
[0052] As shown in FIG. 10, a stack of the heat source portions
110, 120 is formed by alternately stacking the cold-side heat
source portions 120 and the hot-side heat source portions 110,
disposing the pipes 141a between the respective heat source
portions 110, 120 and blazing them integrally. In the stack, the
clearances between both of the heat source portions 110, 120 are
set to be larger than a thickness of the thermoelectric device
130.
[0053] Here, the hot-side heat source portions 140 (at left side in
FIG. 10) pass the hot coolant over the cold-side heat source
portions 120 disposed between the hot-side heat source portions
110. In a same manner, the cold-side heat source portions 150 (at
right side in FIG. 10) pass the cold coolant over the hot-side heat
source portions 110 disposed between the cold-side heat source
portions 120.
[0054] Then, the thermoelectric elements 130 are inserted into
clearances in the blazed stack. The stack of the heat source
portions 110, 120 and the thermoelectric elements 130 are
sandwiched between and supported by a lower plate 160 and an upper
plate 170, then the stake and the upper and the lower plates 160,
170 are fastened by a plurality of bolts 181.
[0055] In this embodiment, by using the pipe 141a provided with the
bellows 142a for forming the respective communicators 140, 150,
intervals between the respective heat source portions 110, 120 are
adjusted by the shrinkage of the bellows 142a (the distance
adjusters 140A) when fastening the stack with the bolts 181. Thus,
it is possible to bring the thermoelectric elements 130 in well
contact with the respective heat source portions 110, 120 without
excessive deformation.
[0056] In this second embodiment, the respective pipes 141a are in
contact with the hot-side heat source portions 110 and the
cold-side heat source portions 120 in contrast to the first
embodiment, causing a small amount of thermal transfer between the
hot coolant and the cold coolant. However, the second embodiment
does not require the O-ring 143, and the two kinds of the
large-diameter pipe 141 and the small-diameter pipe 142 in the
first embodiment is unified into one kind of pipe 141a, so as to
reduce the kind of the components.
Third Embodiment
[0057] A third embodiment of the present invention is shown in FIG.
11. The third embodiment, in contrast to the first embodiment, a
stack of the hot-side heat source portions 110, the cold-side heat
source portions 120 and the thermoelectric elements 130 sandwiched
between the lower plate 160 and the upper plate 170 is enclosed by
a vacuum container 190 that keeps an internal space thereof to an
approximately vacuum state.
[0058] A heat transfer is reduced in a vacuum compared to that in
the air, so as to reduce the temperature difference between the
both heat source portions 110, 120 caused by the thermal
dissipation from the hot-side heat source portions 110 to the
outside and by the thermal absorption by the cold-side heat source
portions 120.
[0059] When the vacuum container 190 is not adopted and the
cold-side heat source portions 120 are colder than the outer air,
the water vapor in the air is condensed on the surface of the
cold-side heat source portions 120, which may cause a short circuit
or corrosion in the thermoelectric elements 130. In the third
embodiment, this issue does not occur.
Other Embodiments
[0060] In contrast to the above first to third embodiments, as
shown in FIG. 12, the thermoelectric generator 100 may have a
heater 45 that exchanges heat between an exhaust gas of the engine
10 and the hot coolant, so as to increase the temperature
difference between the cold coolant and the hot coolant. Thus, by
using the heat of the exhaust gas effectively, the electric power
generation at the thermoelectric elements 130 increases. Further,
the exhaust gas 10 of the engine 100 may be introduced through the
hot-side heat source portions 110, though the drawing is not
shown.
[0061] As the cold fluid in the cold-side heat source portions 120,
the refrigerant circulating in the vehicular refrigerating cycle
apparatus 50 may be used. The refrigerating cycle apparatus 50, as
conventionally known, has a closed circuit having a compressor 51,
a condenser 52, an expansion valve 53 and the evaporator 54
connected in turn by a coolant pipe 55. Then, as shown in FIG. 13,
the cold-side heat source portion 120 is supplied with a
refrigerant in the refrigerating cycle apparatus 50 (after
decompressed by the expansion valve 53), instead of the cold
coolant. Alternately, as shown in FIG. 14, by comprising a cooler
56 between the expansion valve 53 and the evaporator 54, the
refrigerant further cools the cold coolant (fluid). Thus, the
cold-side heat source portion 120 becomes colder than the
conventional refrigerant or coolant for the air conditioner or for
the engine 10.
[0062] This description of the invention is merely exemplary in
nature and, thus, variations that do not depart from the gist of
the invention are intended to be within the scope of the invention.
Such variations are not to be regarded as a departure from the
spirit and scope of the invention.
* * * * *